The ingestion of certain foods by mammals results in flatulence and/or other gastrointestinal symptoms. Certain foods that are extremely flatugenic include milk and milk products, legumes (e.g., peanuts, beans), some cruciferous vegetables (e.g., cabbage, brussels sprouts) and certain fruits (e.g., raisins, bananas, apricots). See Rackis, J. J., "Flatulence Caused by Soya and Its Control through Processing," JAOCS, page 503 (1981). The primary cause of flatulence from the previously mentioned foods is the body's inability to digest certain carbohydrates contained within these foods. The mammalian inability to digest these carbohydrates allows putrefactive bacteria in the large intestine to break down these carbohydrates by fermentation. This results in the formation of excessive levels of rectal gas, primarily carbon dioxide, methane and hydrogen.
The mammalian ability or inability to digest certain carbohydrates depends upon the presence or absence of certain enzymes in the digestive system and the type of carbohydrate to be digested. For example, the human being's ability to secrete the specific enzyme enabling him or her to digest the carbohydrate, lactose (commonly called "milk sugar"), depends upon a number of factors, e.g., age, race and health. Beta-D-galactoside-galactohydrolase (commonly called "beta-galactosidase" or "lactase") is secreted within a human being's digestive system in order to hydrolyze lactose (a molecule which contains the beta-galactoside linkage) into its digestible monosugars, glucose and galactose. When beta-galactosidase activity is not present in sufficient quantities in order to hydrolyze lactose, in vitro treatment of milk or oral administration of microbial beta-galactosidase(s) for in vivo use duplicates the function of the naturally occurring neutral intestinal beta-galactosidase found on the gut wall (known as intestinal lactase).
Lactaid Inc. of Pleasantville, N.J., has been providing a beta-galactosidase in various forms, since approximately 1974, for the in vitro and in vivo treatment of milk. In vitro treatment of milk with beta-galactosidase was first performed by the consumer at home. Approximately ten years ago, in vitro treatment of milk was done on a commercial scale by the dairy industry. Since approximately 1984, a beta-galactosidase preparation has been available on a substantial scale by a number of companies, including Lactaid Inc., for in vivo use.
The success of an ingestible form of beta-galactosidase for in vivo use was not entirely surprising, since the ingested enzyme structurally and functionally duplicates beta-galactosidase present within the human digestive system. There was initial concern as to whether an ingested form of beta-galactosidase subject to varying pH levels would operate effectively in the human stomach and/or intestine. The fact that certain dosages of oral beta-galactosidase preparations did indeed substantially digest dietary lactose in the stomach and small intestine of persons lacking the natural form of this enzyme showed that at least some enzymes from microbial sources were not inactivated by the conditions of acidity, protein digestion, temperature or motility found in the gastrointestinal tract.
The lactose of milk and milk products is digestible by essentially all mammals during at least part of their lives. But this is not the case with certain sugars contained in legumes and certain fruits. The above-mentioned flatugenic legumes, vegetables, and fruits contain one or more of the carbohydrates: raffinose, stachyose and verbascose. What these three oligosaccharide molecules all have in common is a D-galactose sugar linked to another sugar unit via an alpha-galactoside linkage. Enzymes of the class alpha-D-galactoside-galactohydrolase (commonly called "alpha-galactosidase") have the capacity to hydrolyze this alpha-galactoside sugar linkage. D-galactose is a monosaccharide which can be absorbed by the intestinal cell into the body and thereafter converted to glucose. Humans and other mammals cannot digest the three oligosaccharides to liberate D-galactose, since their digestive systems do not produce alpha-galactosidase.
In vitro use of alpha-galactosidase to render the previously-mentioned oligosaccharides digestible is well known. U.S. Pat. Nos. 3,966,555; 4,241,185; and 4,431,737 disclose methods of producing and/or stabilizing alpha-galactosidase by culturing of various microorganisms. All that these patents disclose or imply is that alpha-D-galactosidase can be used in vitro in food processing and/or by addition to foodstuffs for a period of up to 12 hours. This demonstrates the ability to hydrolyze, in vitro, alpha-D-galactoside-linked sugars.
Further, it is well known to use industrial food processing methods for in vitro hydrolysis of alpha-D-galactoside-linked sugars with the addition of alpha-galactosidase. See Cruz, R. et al. "Microbial alpha-Galactosidase for Soy Milk Processing", 46 Journal of Food Science 1196-1200 (1981). Soaking, fermentation, enzymatic hydrolysis, and germination can also be used to eliminate or digest oligosaccharides. Tests with humans and rats indicate that a combination of such in vitro processes can be used to reduce flatus production. See Rackis, J. J., supra. Also well known in the art is that a technique frequently used in commercial processing, namely canning, increases the in vitro rate of hydrolysis of starch and legumes. See Traianedes, et al., "Commercial Canning Increases the Digestibility of Beans in Vitro and Postprandial Metabolic Response to Them in Vivo", The American Journal of Clinical Nutrition 44: Sep. 1986, pp. 390-397.
There are many problems associated with the in vitro processing of foods containing alpha-D-galactoside-linked sugars with the enzyme alpha-galactosidase in order to hydrolyze said alpha-D-galactoside-linked sugars and thus reduce symptoms in mammals ingesting them. The treatment of intact (unmacerated or unchewed) beans or other vegetables and fruits by an enzymatic means is inefficient and costly. The solid nature of these foods precludes efficient, uniform and effective enzyme activity. Solid foods can be turned into a slurry first for more effective enzyme treatment, but this is time-consuming and sometimes non-appetizing, as it prevents serving the food in its original form.
To applicant's knowledge, no one has ever proposed or attempted the feat of delivering an effective alpha-galactosidase orally for in vivo digestion of raffinose, stachyose or verbascose.